NetSight
high8.0

CVE-2026-3108

Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to sanitize user-controlled post content in the mmctl comman…

Impact

Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to sanitize user-controlled post content in the mmctl commands terminal output which allows attackers to manipulate administrator terminals via crafted messages containing ANSI and OSC escape sequences that enable screen manipulation, fake prompts, and clipboard hijacking.. Mattermost Advisory ID: MMSA-2026-00599

Affected packages

EcosystemPackageAffectedFixed in
gogithub.com/mattermost/mattermost/server/v8>= 11.4.0-rc1, < 11.4.111.4.1

Affected products

VendorProductAffected versions
MattermostMattermost Server
from 10.11.0 before 10.11.11
from 11.2.0 before 11.2.3
from 11.3.0 before 11.3.2
Version 11.4.0

Weakness classification

References